= Reproducible installs =

== mmdebstrap ==

The DebianPkg:mmdebstrap program creates reproducible chroots if the '''SOURCE_DATE_EPOCH''' environment variable is defined.

== debuerreotype ==

The DebianPkg:debuerreotype program creates reproducible chroots.

== debootstrap ==

The DebianPkg:debootstrap program does not create reproducible chroots out-of-the-box.
Commands used:

{{{
for n in 1 2 ; do
  debootstrap --foreign unstable debootstrap-firststage-$n http://httpredir.debian.org/debian/
  cp -al debootstrap-firststage-$n debootstrap-secondstage-$n
  DEBOOTSTRAP_DIR=debootstrap-secondstage-$n/debootstrap debootstrap --second-stage --second-stage-target=debootstrap-secondstage-$n
done
diffoscope debootstrap-firststage-{1,2}
}}}

The first-stage debootstrap for a particular Release file is not reproducible, the debootstrap.log file contains timestamps:

{{{
# diff -Naur debootstrap-firststage-{1,2}
diff -Naur debootstrap-firststage-1/debootstrap/debootstrap.log debootstrap-firststage-2/debootstrap/debootstrap.log
--- debootstrap-firststage-1/debootstrap/debootstrap.log        2014-09-24 10:18:42.472604407 +0800
+++ debootstrap-firststage-2/debootstrap/debootstrap.log        2014-09-24 10:33:57.042221221 +0800
@@ -883,8 +883,8 @@
 Setting up tzdata (2014g-1) ...
 
 Current default time zone: 'Etc/UTC'
-Local time is now:      Wed Sep 24 02:16:57 UTC 2014.
-Universal Time is now:  Wed Sep 24 02:16:57 UTC 2014.
+Local time is now:      Wed Sep 24 02:32:13 UTC 2014.
+Universal Time is now:  Wed Sep 24 02:32:13 UTC 2014.
 Run 'dpkg-reconfigure tzdata' if you wish to change it.
 
 Setting up debconf-i18n (1.5.53) ...
}}}

The second-stage debootstrap is not reproducible, some files are different:

{{{
/etc/machine-id
/var/cache/ldconfig/aux-cache
/var/cache/man/cs/index.db
/var/cache/man/da/index.db
/var/cache/man/de/index.db
/var/cache/man/es/index.db
/var/cache/man/fi/index.db
/var/cache/man/fr/index.db
/var/cache/man/hu/index.db
/var/cache/man/id/index.db
/var/cache/man/index.db
/var/cache/man/it/index.db
/var/cache/man/ja/index.db
/var/cache/man/ko/index.db
/var/cache/man/nl/index.db
/var/cache/man/pl/index.db
/var/cache/man/pt/index.db
/var/cache/man/pt_BR/index.db
/var/cache/man/ru/index.db
/var/cache/man/sl/index.db
/var/cache/man/sv/index.db
/var/cache/man/tr/index.db
/var/cache/man/zh_CN/index.db
/var/cache/man/zh_TW/index.db
/var/log/alternatives.log
/var/log/bootstrap.log
/var/log/dpkg.log
}}}

 * The machine-id should be set on first boot instead by calling {{{systemd-machine-id-setup}}}
 * The dpkg.log and file alternatives.log contain timestamps on each line. If they are stripped then the files are the same.
 * The bootstrap.log file contains two timestamps at the beginning. If they are stripped then the file is the same.
 * man-db databases contain a timestamp (DebianBug:760895).  This will be moved into the database file mtime.

== debian-live images ==

See [[ReproducibleInstalls/LiveImages]]

== debian-cloud images ==

No testing done yet.

== Misc ==

Running debootstrap against snapshot.debian.org will help reproduce when time has passed.

== See Also ==

 * [[https://github.com/lamby/debootstrap/commits/pu/source-date-epoch|reproducible debootstrap]]
 * [[ReproducibleBuilds|Reproducible Builds]]
 * [[ReproducibleBuilds/Contribute#Working_on_installation_media_or_live_systems|bash script to analyze images]]
 * [[https://news.ycombinator.com/item?id=8950891|Discussion on Hacker News]]
 * [[https://chris-lamb.co.uk/posts/free-software-activities-in-july-2016|Reproducible images for Webconverger]] ([[https://www.youtube.com/watch?v=FaBFbkBhnXI|video]])
 * [[https://tails.boum.org/blueprint/reproducible_builds/|Tails reproducible builds blueprint]]